rootboy 

I recently picked up a French thread Campy Nuovo Record bottom bracket lock ring. Who knows why. I tend to collect that French stuff, even though mine are in no danger of wearing out or needing replacement. Anyway, I receive it and curse; "this is no Campy Record lock ring. It's twice as thick as the ones I have on my bikes."

Then I got smart and dug out my Campy catalog #17A . Sure enough, it states. "3.5 mm. Also available in 4. mm and 4.5 mm. So, this one measures 4.5 mm thick.

My question is, what is the application for this? I'll admit, even after reading the Record News pages on Record bottom brackets, and, my Sutherland's 2nd edition, I find all the different variables a bit confusing. Thick cups vs. thin. Different spindle lengths and width between bearing lands, etc., etc. Plus, I just don't have enough experience on enough bikes to have seen all the various applications.

So far I've asked 3 forum members via PM and received some good theories. But I thought I'd throw this up here and see what other experts say.

IthaDan 

Older frames have been faced more than once, so you need [could use] a thicker lockring?

Michael Angelo 

+1

rootboy 

This was MA's theory via PM's , and I think it sounds the most plausible.

If so, it's likely one more useless, to me, ebay purchase.

IthaDan 

(wanted a :confused: smiley here, WTF seems a little coarse)

Are you really running your crankarms so close to the hilt that you can't abide a millimeter of clearance?

rootboy 

Hmm. Not sure how to respond to that but, with both my bottom brackets right at 68 mm, and the axles I'm using, the 3.5 mm lock rings fit right. This one would sit 2 mm proud of the cups, but could be usable in a pinch. Or if I ever get my bottom brackets faced. Which isn't too likely.

IthaDan 

Oh, it's an aesthetic thing.

Your post made it sound like it was a clearance thing, like the crankarm would hit the 4.5mm lockring while it clears the 3.5mm one.

repechage

Campagnolo made in the 70's at least a thicker lock ring. Allegedly, Masi was the first to ask for one.

rootboy 

Oh yeah. It would function OK. But look a little odd, protruding past the cup face. Should be flush, IMO. But I'm picky that way.

And, perhaps this isn't a Nuovo Record era ring, though it was advertised as such. Heck, maybe it's not even a Campagnolo ring.
It looks it but, I dunno.

repechage

I would not question it. I am sure there is someone who would be thrilled to have it in exchange for a thin one where the BB shell was faced a bit below 68 mm wide.

HeyPip

I think that the 4.5mm lock ring was to be used with a 68mm spindle and a 65mm pista (track) bottom bracket shell (with a 110mm rear hub OLD). It was the early 70's and a transition period in BB geometry. A 1.5mm spacer had to be installed behind the fixed cup too, to make it fit correctly. Campy made them but they were not in any catalog I've seen. This was only for Record, thin wall cup bottom brackets iirc.

Pip

Michael Angelo 

I would like all the lock rings I use to be a bit on the thick side. Much easier for the tool to grab.

rootboy 

That's a good point, M.A. And as for questioning it, well, no, I'm not about to throw it out with the trash. Just wondering what application is was intended for. There's some interesting input from HeyPip. Thanks. That's what I was curious about. Whether it was intended strictly for a "repair" situation, ie; , a BB shell faced below nominal spec, or, whether it could have been also used with other spindle/axle combinations. For instance, like using a spindle intended for a 70 mm shell in a 68 mm shell. ??? Or, is that completely wrong thinking?

It didn't cost much, and I'll definitely hang on to it. Who knows?